frequency optimization
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- MeSH
- dechová frekvence fyziologie MeSH
- dechová práce fyziologie MeSH
- financování organizované MeSH
- mechanické ventilátory MeSH
- péče o pacienty v kritickém stavu metody MeSH
- teoretické modely MeSH
- umělé dýchání metody přístrojové vybavení MeSH
- vysokofrekvenční proudová ventilace metody přístrojové vybavení MeSH
Nádory kůže mají v posledních letech narůstající incidenci. Diagnostika je dána především klinickým vyšetřením. Přesnost závisí na zkušenostech vyšetřujícího lékaře. Vychází se z anamnestických údajů, makroskopického nálezu, někdy i s použitím lupy. Tím se získá dvourozměrný obraz ložiska. Chybí však informace o tloušťce, která je klíčová pro optimální plánování terapeutického postupu, zejména laserového nebo kryochirurgického. Ultrazvukové přístroje se používají v klinické medicíně několik desítek let. Jejich využití v oblasti dermatologie je novější. Kromě diagnostiky tumorů se dále využívají k monitorování léčebného efektu u zánětlivých onemocnění v oblasti dermis, dále je možná detekce změn v oblasti subcutis. Rozšířené je využití metody v experimentální medicíně. Nejčastěji používané sondy pracují s frekvencí 20 MHz, umožňují zobrazit struktury v hloubce až 7 mm. Hlavní echogenní strukturou dermis je síť kolagenních vláken, její alterace se projeví změnou v ultrazvukovém obraze. V některých konkrétních případech může toto vyšetření přispět i k diferenciální diagnóze, hlavní pole výtěžnosti vyšetření je ale v detekci strukturálních změn. Cílem práce je představit našim dermatologům podrobněji možnosti využití a omezení této moderní neinvazivní vyšetřovací metody. Díky snižujícím se pořizovacím nákladům se může stát běžněji dostupnou.
In last years the incidence of skin tumors is increasing. Skin tumor diagnostics is based mainly on clinical examination and its accuracy depends on an experience of dermatologist. Patient's history, macroscopic findings, sometimes with use of magnifying glass, are considered and thus two - dimensional picture of lesion is obtained. However, the information about tumour thickness, which is a basic clue to optimal therapy planning, especially considering laser or cryosurgery treatment, is missing. Ultrasound devices have been used for several decades in clinical medicine. Their utilization in dermatology is rather recent. Except for tumour diagnostics, they are used for a therapeutical effect monitoring of inflammatory diseases localized in dermis or to diagnose changes in the subcutaneous tissue. The method is widely used in experimental medicine. The mostly used probes working with the frequency of 20 MHz enable to imagine structures 7 mm deep. The main echogenous structure of the dermis is a network of collagen fibres – its alteration causes a change in the ultrasound image. In particular cases the method could contribute to the differential diagnostics but the main scope is still in the detection of structural changes. This article aims to introduce the possibilities and limitations of this new non-invasive examination method to our dermatologists. By virtue of decreasing acquisition costs it might become readily available.
UNLABELLED: Purpose/Aim : High-frequency oscillatory ventilation (HFOV) is a method of ventilation that theoretically achieves the goals of lung protective ventilation in acute respiratory distress syndrome (ARDS) patients. It is characterized by a rapid delivery of small tidal volumes at high frequencies oscillating around a continuous distending pressure (CDP). Optimization of CDP is not an easy task and it is titrated empirically in the clinical practice. The aim of this study is to investigate whether the level of CDP consistently affects the shape of the partial pressure of oxygen (PaO2) response to stepwise changes in CDP during HFOV of healthy and ARDS-induced pigs. MATERIALS AND METHODS: We performed two stepwise maneuvers of CDP in 14 pigs: one before and one after the lung lavage, inducing ARDS. For each CDP step performed, we fitted a segment of PaO2 curve with a one-term power model. RESULTS: PaO2 course follows shapes modeled by root, linear, quadratic, and cubic functions for values of PaO2 ≤ 110 mmHg and PaO2 ≤ 200 mmHg, before and after the lung lavage, respectively. PaO2 course follows a shape modeled exclusively by a root function for values of PaO2 > 110 mmHg and PaO2 > 200 mmHg, before and after the lung lavage, respectively. It is not possible to describe a relationship between the shape of the PaO2 course and the values of CDP. CONCLUSIONS: The PaO2 curve may give information about the level of recruitment of alveoli, but cannot be used for optimization of CDP level during HFOV in healthy and ARDS lung model pigs.
- MeSH
- analýza krevních plynů metody MeSH
- bronchoalveolární laváž metody MeSH
- dechový objem fyziologie MeSH
- kyslík metabolismus MeSH
- modely nemocí na zvířatech MeSH
- prasata MeSH
- syndrom dechové tísně metabolismus patofyziologie MeSH
- tlak MeSH
- umělé dýchání metody MeSH
- výměna plynů v plicích fyziologie MeSH
- vysokofrekvenční ventilace metody MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Článek se zabývá problematikou léčby hemofilie, profylaktickou léčbou, rizikem vzniku inhibitoru koagulačních faktorů a možnostmi jeho minimalizace. Sdělení rozebírá farmakokinetické profilování, které se ukazuje jako účinný nástroj k optimalizaci léčby a k efektivnímu využití nákladů na léčbu. Tento přístup k léčbě umožňuje dávku a frekvenci dávkování určit na základě farmakokinetických dat konkrétního pacienta.
The article deals with the treatment of hemophilia, prophylactic treatment, risk of development of the coagulation factor inhibitor, and the options concerning its minimization. Pharmacokinetic profiling is being discussed, seeming to be an effective instrument allowing for treatment optimization and effective resource allocation. This approach makes it possible to define the dose and frequency of its application based on the pharmacokinetic data of any individual patient.
- Klíčová slova
- krvácení do kloubů, biologická poločas eliminace, myPKFiT, farmakokinetické profilování,
- MeSH
- dítě MeSH
- faktor IX terapeutické užití MeSH
- faktor VIII * ekonomika farmakokinetika terapeutické užití MeSH
- hemofilie A * farmakoterapie komplikace MeSH
- hemofilie B farmakoterapie komplikace MeSH
- koagulační faktory antagonisté a inhibitory MeSH
- lidé MeSH
- metabolická clearance MeSH
- nemoci kloubů * etiologie prevence a kontrola MeSH
- odběr vzorku krve využití MeSH
- on-line systémy MeSH
- poločas MeSH
- protilátky imunologie krev MeSH
- software MeSH
- teoretické modely MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
The main goal of this study is to demonstrate the possibility of training the Neural Network (multilayer perceptron) classifier and preprocessing units simultaneously, i.e., that properties of preprocessing are chosen automatically during the training phase. In the first realization step, adaptive recursive estimation of the power within a frequency band was used as a preprocessing unit. To improve the efficiency of special units, the power and momentary frequency estimation was replaced by methods that are based on adaptive Hilbert transformers. The strategy was developed to obtain optimized recognition units that can be efficiently integrated into strategies for monitoring the cerebral status of neonates. Therefore, applications (e.g., in neonatal EEG pattern recognition) will be shown. Additionally, a method of minimizing the error function was used, where this minimization is based on optimizing the network structure. The results of structure optimization in the field of EEG pattern recognition in epileptic patients can be demonstrated.
Extremely preterm infants often develop chronic lung disease (CLD) characterized by heterogeneous aeration; poorly supported, floppy airways; and air trapping. High-frequency jet ventilation (HFJV) with high end-expiratory pressure (optimal lung volume strategy [OLVS]) may improve airway patency, lead to better gas distribution, improve gas exchange, and facilitate extubation. In a pilot trial, this study sought to explore the effect of HFJV on oxygenation, ventilation, and ease of extubation in preterm infants with evolving CLD and refractory respiratory failure (RRF). From September 2002 to October 2004, 12 episodes of RRF developed in 10 ventilated extremely immature infants with evolving CLD (10 on conventional and two on high-frequency oscillation). Chorioamnionitis was confirmed in all infants, patent ductus arteriosus was ligated in five patients, and UREAPLASMA UREALYTICUM was cultured from trachea in four patients. HFJV with OLVS was initiated when oxygenation index (OI) > 10 or exhaled tidal volume (V TE) >or= 7 mL/kg were required to maintain partial pressure of carbon dioxide, arterial (Pa CO2) < 60 mm Hg. Inspiratory time (0.02/s) and frequency (310 to 420/min) were set initially with adjustment of pressure amplitude to keep Pa CO2 between 45 and 55 mm Hg. Ventilatory stabilization and weaning from mechanical ventilation with extubation to nasal continuous positive airway pressure (CPAP) were the goals of this approach. Gas exchange data were analyzed by Analysis of variance for repeated measures. Ten patients on 11 occasions of RRF were extubated to nasal CPAP successfully in a median of 15.5 days. Nine of 10 patients survived (one died of pentalogy of Cantrell), all required supplemental O2 at 36 weeks. Pa CO2 decreased within 1 hour after the initiation of HFJV, and OI decreased by 24 hours. Both remained significantly lower until successful extubation ( P < 0.02). Compared with conventional ventilation or high-frequency oscillatory ventilation, HFJV used with OLVS appears to improve gas exchange and may facilitate weaning from mechanical ventilation (MV) in extremely immature infants with evolving CLD. These encouraging pilot data need to be confirmed in a larger clinical trial.
- MeSH
- chronická nemoc MeSH
- klinické křížové studie MeSH
- lidé MeSH
- nemoci nedonošenců * terapie MeSH
- novorozenec s extrémně nízkou porodní hmotností MeSH
- novorozenec MeSH
- pilotní projekty MeSH
- plicní nemoci * terapie MeSH
- plicní ventilace MeSH
- progrese nemoci MeSH
- spotřeba kyslíku MeSH
- vysokofrekvenční proudová ventilace * metody MeSH
- Check Tag
- lidé MeSH
- novorozenec MeSH
- Publikační typ
- klinické zkoušky MeSH
- práce podpořená grantem MeSH
Ultrazvukové přístroje se používají běžně v medicínské diagnostice v mnoha oborech, jejich použití v dermatologii je relativně nové. Důležitým cílem v dermatologické diagnostice je včasné rozpoznání tumorů, zejména melanomu. Tyto přístroje mohou v mnoha případech pomoci upřesnit diagnózu, rozsah tumoru a tím i lépe plánovat léčebný postup. Vyšetření ultrazvukem je též přínosné při monitorování léčby, např. zánětlivých dermatóz. Ultrazvukem je dále například možné vyšetřovat působení kortikoidů na kůži. Další možnosti využití jsou zkoumány. Nejčastěji používaná frekvence je 20 MHz, která optimálně zobrazí dermální struktury. Vyšetření ultrazvukem je minimálně zatěžující pro pacienta, je nebolestivé, lze jej podle potřeby opakovat. Ultrazvuk má možnost stát se běžnou diagnostickou metodou v dermatologii.
Ultrasound scanners have become routine in lot of disciplines, their use in dermatology is relatively new. A major focus in dermatology is the early detection of skin tumors, namely melanoma. This equipment is useful to set the diagnose and give the information about the tumor thickness, which is important for better therapy planning. The method is widely used for a therapeutical effect monitoring, for example of inflammatory diseases. It is possible to follow effects of corticosteroids on skin by ultrasound scanning and many more. Further possibilities of the method are investigated. The mostly used equipments work with the frequency of 20 MHz, wich imagine structures of dermis optimal. Ultrasound scanning is harmless for the patient and can be repeated in case of need. Ultrasound can become widespread diagnostic method in dermatology.
- Klíčová slova
- A-scan, B-scan, C-scan, kožní tumory, zánětlivé dermatózy,
- MeSH
- kožní nemoci ultrasonografie MeSH
- kůže MeSH
- nádory kůže ultrasonografie MeSH
- ultrasonografie metody MeSH
This work aims to synthesize akaganeite nanoparticles (AKNPs) by using microwave and use them to adsorb Congo red dye (CR) from the aqueous solution. The AKNPs with an average particle size of about 50 nm in width and 100 nm in length could be fabricated in 20 min. The effects of pH, CR initial concentration, adsorption time, and adsorbent dosage on the adsorption process were investigated and the artificial neural network (ANN) was used to analyze the adsorption data. The various ANN structures were examined in training the data to find the optimal model. The structure with training function, TRAINLM; adaptation learning function, LARNGDM; transfer function, LOGSIG (in hidden layer) and PURELIN (in output layer); and 10 neutrons in hidden layer having the highest correlation (R2 = 0.996) and the lowest MSE (4.405) is the optimal ANN structure. The consistency between the experimental data and the data predicted by the ANN model showed that the behavior of the adsorption process of CR onto AKNPs under different conditions can be estimated by the ANN model. The adsorption kinetics was studied by fitting the data into pseudo-first-order, pseudo-second-order, Elovich, and intraparticle diffusion models. The results showed that the adsorption kinetics obeyed the pseudo-second-order model and governed by several steps. The adsorption isotherms at the different temperatures were studied by fitting the data to Langmuir, Freundlich, and Temkin isotherm models. The R2 obtained from the Langmuir model was above 0.9 and the highest value in three of four temperatures, suggesting that the adsorption isotherms were the best fit to the Langmuir model and the maximum adsorption capacity was estimated to be more than 150 mg/g. Thermodynamic studies suggested that the adsorption of CR onto AKNPs was a spontaneous and endothermic process and physicochemical adsorption. The obtained results indicated the potential application of microwave-synthesize AKNPs for removing organic dyes from aqueous solutions.
